1. Field of the Invention
The present invention is directed generally to estimating a geographical location of a mobile station connected to a mobile wireless network. Specifically, the present invention is directed to using electronic surveillance events detected in the mobile wireless network to automatically generate a location estimate of a mobile station associated with the surveillance event and to automatically provide the location estimate to an appropriate law enforcement agency.
2. Description of the Related Art
Most mobile wireless networks today are equipped with enhanced emergency services (E911) resources that automatically provide emergency service providers with the location of a mobile station making an emergency call to 911. Some mobile wireless networks provide non-emergency Location Based Services (LBS) that use the same or similar resources as the E911 resources.
In the course of performing surveillance on a particular mobile station, law enforcement agencies sometimes need to determine the location of the mobile stations. Most mobile wireless networks today can automatically provide law enforcement agencies the identity of the serving cell sector at the beginning and end of a call as part of compliance with the Communications Assistance for Law Enforcement Act of 1994 (CALEA). Some mobile wireless networks today can also provide time-based interval tracking to generate automated location estimates of particular mobile stations. For example, a wireless network may be configured to request location update of a particular mobile station every fifteen minutes and send that location estimate to the law enforcement agency that requested it. However, in some situations the targeted mobile station is only powered on for very short periods of time. In other cases a law enforcement agency may want to correlate the location of a mobile station to particular activities (e.g., registering the mobile station with the network during powering up the mobile station, originating a call, sending a text message, or accessing a website, etc.). For example, a law enforcement agency may be confronted with a kidnapper who only activates a prepaid mobile on the network for thirty seconds to call in ransom demands and then removes the battery. Current methods are inadequate for these needs.